High Temperature Fan Construction¶

Run the High Temperature Fan Construction MicroSim Fullscreen

About This MicroSim¶

This MicroSim puts seven numbered markers on FanPedia's general construction drawing for high temperature centrifugal fans (page 110). The large drawing is a belt driven centrifugal fan on its base, with its housing prepared for insulation. Down the left side are three close-ups of the drive end, where the shaft leaves the hot housing: the top one shows the shaft seal, shaft cooler and bearing of the high temperature style pedestal, and the bottom one shows the same corner on a housing studded with insulation pins, with a guarded open frame around the shaft cooler. The middle close-up (a shaft cooler with a stuffing box or mechanical seal) carries no marker.

The seven parts are the shaft seal, bearing, shaft cooler, insulation pins, raised access door, safety screen and cooler box. On a wide screen a label column with leader lines sits to the right of the drawing; on a narrow screen the labels move below it as a numbered list.

The quiz describes each part by its job ("Select the part that sheds heat from the shaft before it reaches the bearings.") instead of naming it, in a shuffled order. You get two attempts per prompt. The first wrong answer shows a hint about where to look; the second reveals the part and counts as missed. Mastery is 6 of 7 correct on the first attempt. Explore mode is never scored.

How to Use¶

Explore mode (the starting mode). Point at a numbered marker, or Tab to it, to see the part's name and description in the panel below the drawing. Click it (or press Enter) to open it; opened parts get a ✓ in the label list and the counter shows how many of the 7 you have visited. Clicking a name in the label list opens that part too.
Quiz mode. Press Quiz. The labels and leader lines disappear and a prompt describes one part:
- Correct: "✓ Correct:" with the part name and its description; the marker turns green with a ✓ badge and its label comes back.
- Wrong on the first attempt: "✗ Not quite.", the name of the part you picked, and a hint. The hint never names the answer.
- Wrong on the second attempt: the answer is marked "Answer" and named, and the prompt counts as missed.
Press Next prompt after each answer. The toolbar shows "Parts correct: n of 7".
After the seventh prompt, the summary shows your first-attempt score, whether you reached mastery (6 of 7), and each missed prompt with its answer. Retry missed practises only the misses (not scored), Start over reshuffles and resets the score, and Back to explore returns to the labels.

Keyboard: Tab moves through the markers in number order and then the buttons; Enter or Space selects a marker. After an answer, focus moves to Next prompt, so Enter goes on.

Data label: "Drawing: FanPedia, Twin City Fan, p. 110", shown under the drawing.

Iframe Embed Code¶

You can add this MicroSim to any web page by adding this to your HTML:

<iframe src="https://moroshek.github.io/FanTASTIC-textbook/sims/ch21-high-temp-construction-overlay/main.html"
        height="805px"
        width="100%"
        scrolling="no"></iframe>

Lesson Plan¶

Learning Objective¶

The learner will identify the seven labeled high temperature construction features of a centrifugal fan (shaft seal, bearing, shaft cooler, insulation pins, raised access door, safety screen and cooler box) on FanPedia's drawing, given each feature's job (Bloom: Remember, verb: identify).

Audience¶

Adult professional development: new application engineers, sales staff, representatives and facilities staff.

Duration¶

10 minutes

Prerequisites¶

Chapter 21, sections "How Heat Moves Through a Fan" and "Shedding and Blocking Heat at the Shaft" (shaft cooler, cooler box, insulation pins).
Chapter 3, sections "Access Door" (raised access door) and "Bird and Safety Screens".
Chapter 16, section "Shaft Seals".

Activities¶

Explore (3 min): Open all seven parts. Trace the shaft in the top close-up from the housing wall outward: which part meets the shaft first, which comes next, and which part is all of that there to protect?
Compare (2 min): Compare the top and bottom close-ups. What was added around the shaft cooler once the housing was insulated, and why is that area left open?
Quiz (3 min): Switch to quiz mode and find all seven parts from their jobs without going back to explore mode.
Classify (2 min): Go on to High Temperature Fan Heat Path, which sorts the shaft cooler, cooler box and insulation pins (and seven other parts) by whether they block heat, shed heat or allow growth.

Common Misconceptions Addressed¶

A cooler box is an insulated enclosure: it is an uninsulated open area left around the shaft cooler so the cooler has air to shed heat into.
Insulation pins are themselves insulation: they only hold the field- or vendor-applied insulation on the housing.
The shaft cooler cools the airstream: it sheds the heat that has travelled along the shaft from the airstream, to protect the bearings.

Assessment¶

First-attempt score shown in the summary as "First-attempt score: n of 7"; mastery is 6 of 7 on the first attempt.
Pointing at markers and opening infoboxes in explore mode is exploration, not evidence.
Follow-up question: a customer orders this fan with aluminum clad insulation. Which part on the drawing would otherwise be buried, and which feature keeps it working?

References¶

FanPedia: The Fan & Blower Encyclopedia (PDF) - Twin City Fan; p. 110 is the high temperature general construction drawing used here (cooler box, insulation pins, safety screen, raised access door), p. 90 the high temperature style pedestal, p. 117 the raised access door and p. 192 the shaft cooler.
FanPedia online - Twin City Fan's online version of the encyclopedia.
Chapter 21: High Temperature, Leak-Tight and RTO Construction - the section "Shedding and Blocking Heat at the Shaft", where this MicroSim is embedded.
Chapter 3: Basic Fan Anatomy and Chapter 16: Bearings, Shafts and Shaft Seals - the safety screen, the raised access door and the shaft seal.
High Temperature Fan Heat Path - the companion sim that classifies these parts by job.